The present invention relates generally to charging units or battery chargers and more particularly to voltage-reducing power packs.
Small battery chargers have been used in increasing numbers in recent years, as hand-held tools and appliances using small rechargeable batteries have become more common. Their economical manufacture with sturdy trouble-free characteristics has presented problems.
These voltage-reducing units generally include a transformer housed within a casing with a primary winding having input leads and a secondary winding having output leads. The input leads are usually connected to some type of prong structure which can be inserted into the conventional electrical outlet, while the output leads are connected to a cord which can be plugged into the unit that is to be recharged.
Because of the large market for these types of units, considerable competition has been developed among manufacturers.
While such units are being offered by domestic manufacturers, many units are still being sold by foreign manufacturers. The main reason purchasers select foreign units over domestic units is the fact that the cost of the domestic unit heretofore has been substantially higher than the cost of the foreign unit. Thus, domestic manufacturers are constantly striving to develop a unit that meets all of the stringent Underwriters Laboratory test requirements and can still be manufactured at a competitive cost.